By Lynne Friedmann
An ambitious new study describes the full chain of events by which ocean biogeochemical changes triggered by manmade greenhouse gas emissions may cascade through marine habitats and organisms, penetrating to the deep ocean and eventually influencing humans.
Previous analyses have focused mainly on ocean warming and acidification, underestimating the biological and social consequences of climate change. Factoring in predictable changes such as the depletion of dissolved oxygen in seawater and a decline in productivity of ocean ecosystems, the new study shows that no corner of the world ocean will be untouched by climate change by 2100. Because some 470 million to 870 million of the world’s poorest people rely on the ocean for food, jobs and revenues, the consequences of these co-occurring changes are massive: Everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry.
The conclusions derive from a 28-person international collaboration — that includes Scripps Institution of Oceanography at UC San Diego — of climate modelers, biogeochemists, oceanographers and social scientists.
— Findings appear in the journal PLOS Biology. News release at
Costly cigarettes and smoke-free homes
Researchers at the UC San Diego School of Medicine have found that a combination of expensive cigarettes and living in a smoke-free home is most effective in reducing smoking by low-income individuals — a demographic in which tobacco use has remained comparatively high.
The study found that costly cigarettes — $4.50 or more per pack — were associated with lower consumption. In states where the average price for cigarettes is $3.20 or less per pack, all smokers — those living below the federal poverty level as well as the wealthy — will smoke more than those who live in a state with higher prices.
While price is a deterrent to smoking, successfully quitting (90 or more days) was found more likely to occur when smokers agree to keep a smoke-free home. Not only were they more likely to reduce smoking but, once they quit, they were less likely to relapse.
Findings are derived from the 2006-07 Tobacco Use Supplement to the Current Population Survey, a monthly nationally representative cross-sectional survey conducted by the U.S. Census Bureau. The researchers analyzed three sets of supplemental data containing responses from more than 150,000 participants aged 18 and older who self-reported both income and smoking habits.
— The study appears in the American Journal of Public Health. News release at
Rocket engine courtesy of 3D-printing
Recently, a team of local engineering students successfully test-fired a rocket engine. What makes the achievement notable is that it marks the first time that a university-led group has designed and built a rocket engine using 3D-printer technology.
The design of liquid-propellant rockets is highly complex and detailed. Thus, the UC San Diego chapter of Students for the Exploration and Development of Space (SEDS) set out a formidable task for itself in taking on the project.
NASA and private groups have been investigating how to use 3D printing to reduce the cost and design constraints of manufacturing rocket parts. NASA recently achieved a first by testing a 3D-printed rocket fuel injector. The UCSD students went a step further by designing an entire engine that was then manufactured on a specialty 3D printer. The engine was primarily financed by NASA’s Marshall Space Flight Center in Huntsville, Ala. Students also worked closely with Carlsbad-based Flometrics (www.flometrics.com), an engineering firm specializing in fluid dynamics and thermodynamics.
— More information at
Lynne Friedmann is a science writer based in Solana Beach.